Field Tests and Observation of Wave-Loading Influence on Erodibility of Silty Sediments in the Huanghe (Yellow River) Estuary, China

Abstract

(1) Simulations of wave action and erosion, using a wave-producing device and a recirculating flume, were established on the Haigang mudflat, in the Yellow River estuary, China, along with the geotechnical-parameter tests of the water content, bulk density, undrained shear strength, penetration strength, and grain-size distribution. Moreover, the variety of seabed morphological characteristics under different wave actions was also observed in field. The experimental results showed that the erodibility of the silty sediment was significantly affected by the cyclic wave loading in Yellow River estuary. The erodibility varied with the changing wave loading and was closely related to the liquefaction and topography characteristics of the surficial sediment, which restricted the physical and mechanical properties of the sediment. Additionally, the wave loading transformed the sediment components and the size grading, which also had a remarkable effect on the erodibility. Increasing the length of the time vibration during wave loading clearly reduced erosion resistivity, although fluctuations appeared in the overall downward trend, consistent with the strength indexes of the silty sediment. The other geotechnical parameters, size grading, and sediment components show the wave's dynamic variation with the changing conditions, but no clear internal relationship could be found between the varying physical parameters and the variation in erosion during the changing conditions of the wave during the experiments.